Building construction



Sept. 1969 A. c. CLEMENTS 3,464,176

. BUILDING CONSTRUCTION Filed Dec. 19, 1966 5 Sheets-Sheet 1 Sept. 2,1969 A. C. CLEMENTS BUILDING CONSTRUCTION 5 Sheets-Sheet 7,

Filed Dec. 19. 1966 FIG. 6

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BUILDING CONSTRUCTION Filed Dec. 19. 1966 5 Sheets-Sheet 5 United StatesPatent 3,464,176 BUILDING CONSTRUCTION Arthur C. Clements, Santurce,Puerto Rico, assignor to Interstruct Corporation, Carolina, Puerto Rico,a corporation of Puerto Rico Filed Dec. 19, 1966, Ser. No. 602,647 Int.Cl. E0411 5/18, 5/06 us. or. 52-251 14 Claims ABSTRACT OF THE DISCLOSUREThis invention relates to building construction and more particularly toa monolithic building structure of concrete or similar material.

Various construction procedures are in use at the present time for theerection of single and multi-story concrete buildings. In one type ofconstruction, forms for the concrete are erected at the building site,and the concrete is poured in place to produce either a substantiallycomplete building in a single operation or a wall or floor slabtherefor. Other procedures utilize pre-cast concrete blocks which aretransported from the factory to the site. In some cases, the blocksserve as the loadsupporting structure for the building and are cementedtogether through the use of a suitable mortar, while in other situationsthe blocks act as fillers for poured-in-place concrete and do notperform a structural function.

Heretofore, difllculties have been encountered in the provision ofmonolithic building structures of concrete or similar material. Withrespect to the poured-in-place type of construction, for example, thenecessary forms for the concrete often were not readily transportable tothe building site, with the result that complicated and time consumingprocedures frequently were needed to construct or assemble the forms atthe site. Also, although the pouring of the concrete between the formsto produce a substantially complete building in asingle operationresults in a uniform monolithic structure and has other importantadvantages, the excessive bulk of the forms and the quantity of concreterequired has limited the use of these latter techniques particularly formultistory construction. For construction procedures which utilizeprecast concrete blocks, one of the major difliculties encounteredheretofore has been in the fastening of the blocks together to providean integral structural unit capable of withstanding the various shearstresses which exist between adjacent blocks. In addition, and this hasbeen of special moment in the construction of floors and walls in whichthe faces of the blocks are exposed, difficulties have been encounteredin the proper alignment of the blocks and in the provision of areasonably pleasing appearance to the exposed surfaces. Furthermore, itoften is desirable to conceal conduits or ducts within the structure ofthe slabs forming the floors and walls, and many previous types ofconstruction have proved deficient in these respects.

One general object of this invention, therefore, is to provide a new andimproved monolithic structure for the floor or wall slabs of a building.

More specifically, it is an object of this invention to provide suchstructure utilizing both concrete blocks or other preformed members anda poured-in-place material which each form a structural, load-bearingportion of an integral building slab.

Another object of this invention is to provide a structure of thecharacter indicated which exhibits increased resistance to shearstresses not only in the plane of the slab but also in directionsperpendicular thereto.

A further object of the invention is to provide a building slabincluding a series of preformed members which may be quickly and easilyaligned and present a pleasing and attractive appearance.

Still another object of this invention is to provide a building slab inwhich the necessary Wiring, plumbing, heating and cooling ducts or otherconduit may be readily concealed within the slab.

A still further object of this invention is to provide a precastbuilding block which is economical to manufacture and readilytransportable to the building site.

SUMMARY formed members and the poured material have a compositestructural function.

In accordance with one feature of the invention, the side wall of eachof the preformed members includes a keyway having side portions whichare oriented in acute angles with respect to the plane of the buildingslab. The cementitious material which is poured between adjacent membersextends into the keyways to form twoway shear keys. The arrangement issuch that the keys resist shear stresses in the plane of the slab andalso in directions perpendicular thereto, with the result that theload-supporting capabilities of the slab are substantially improved.

In accordance with another feature of the invention, in certainparticularly advantageous embodiments, each of the side walls for thepreformed members extends in a plane which meets the plane of thebuilding slab at an acute angle, thereby defining a generally V-shapedgroove between the members which accommodates the pouredin-placematerial. In several good arrangements, each member includes aperipheral flange having a bevelled edge portion which greatlyfacilitates the alignment of the members to form the slab and alsopresents a pleasing appearance in cases in which the surfaces of themembers are exposed.

In accordance with a further feature of certain good embodiments of theinvention, the side walls of the individual preformed members arecomparatively thin and form a hollow construction. The portions of thewalls which define the central faces of the keyways are substantiallythinner than the remaining wall portions. The members are extremelylight in weight, and the central faces of the keyways may be readilyremoved at the construction site to gain access to the interior of themembers, thus enabling the rapid and straight-forward installation ofconcealed conduits and ducts.

In accordance with a still further feature of the invention, in someembodiments, the preformed members are assembled into a floor slab andare supported by upright preformed columns. Each of the columns includesan integral, substantially fiat upper section which extends in the planeof the slab in contact with the peripheral flanges of the adjacentmembers. The columns are held in place by the poured cementitiousmaterial in a manner such that their upper sections form a part of themonolithic structure.

The present invention as well as further objects and features thereofwill be understood more clearly and fully from. the followingdescription of certain preferred embodiments, when read in conjunctionwith the accompanying drawings, in which:

FIGURE 1 is a perspective view of a precast concrete block constructedin accordance with one illustrative embodiment of the invenion;

FIGURE 2 is a side elevational view of the block shown in FIGURE 1;

FIGURE 3 is a top plan view of the block, with a portion broken away;

FIGURE 4 is a perspective view of a precast concrete column forsupporting a floor slab assembled from a series of the blocks of FIGURE1;

FIGURE 5 is a side elevational view of the column shown in FIGURE 4,with a portion broken away, together with reinforcing rods useful inproviding additional support;

FIGURE 6 is a top plan view of the column;

FIGURE 7 is a side elevational view, with certain parts shown brokenaway and in section, of a monolithic building structure including anassembly of blocks and columns of FIGURES 1-6, together with an assemblyof reinforcing rods for the structure;

FIGURE 8 is a fragmentary top plan view of the building structure ofFIGURE 7;

FIGURE 9 is a horizontal sectional view taken along the line 99 inFIGURE 5;

FIGURE 10 is a horizontal sectional view taken along the line 10-10 inFIGURE 5;

FIGURE 11 is an enlarged side elevational view of one of the reinforcingrod assemblies shown in FIG- URE 7;

FIGURE 12 is a fragmentary elevational view, with certain parts shown insection, of a monolithic building snucture including precast concreteblocks constructed in accordance with another illustrative embodiment ofthe invention; and

FIGURE 13 is a partially schematic elevational view of apparatus forcasting the blocks.

Referring to FIGURES 1-3 of the drawings, there is shown a precastbuilding block indicated generally at The block 20 is fabricated fromconcrete or similar material and in the illustrated embodiment is ofsquare configuration. Although the dimensions of the block may varywidely depending upon the particular type and size of the building inwhich it is to be used, the block illustratively may be about four feetby four feet and approximately one foot thick. In order to reduce itsweight and to facilitate the installation of conduits and ducts, theblock is of hollow construction. Thus, an internal cavity 21 is formedbetween the upper face 22 and the lower face 23 of the block, in amanner that will become more fully apparent hereinafter, and a series ofconcrete posts 25 are disposed therein to provide additional support.The faces 22 and 23 extend in smooth flat planes and may be exposed toprovide exterior and interior wall surfaces for the building.

The building block 20 includes four side walls 26. Each of the sidewalls 26 extends in a plane which is angularly disposed with respect tothe block faces 22 and 23 and slopes downwardly and outwardly at anacute angle A with respect to the building slab in which the block is to4 be incorporated. In the illustrative form of the block shown inFIGURES 1-3, the angle A is of the order of eighty-four degrees.

A keyway 30 is formed in the central portion of each of the side walls26 of the block 20. The keyway 30 is defined by two flat side surfaces31 and 32 and a flat central surface 33 which is parallel to the sidewall. As best shown in FIGURES 2 and 3, the surfaces 31 and 32 divergeaway from one another in a direction from the center of the slab to thecorresponding side wall 26, thus greatly facilitating the strippingoperation described in more detail below. The surfaces 31 and 32 are inconverging relationship with each other in a direction from one face ofthe slab to the other and extend in planes which meet the plane of thebuilding slab at opposite but equal acute angles B. The angles B are ofthe order of seventy-six degrees and preferably are slightly less thanthe angle A between the plane of the side wall and the plane of theslab. The thickness of the central portion 33 of the keyway 30 issubstantially less than that of the corresponding side wall, forpurposes that will be described more fully hereinafter.

The block 20 is provided with a square peripheral flange 35 adjacent itslower face 23. This flange includes an upper bevelled portion 36 and alower bevelled portion 37 which slope toward each other such that theplanes of the bevelled surfaces meet at a comparatively large angle. Thecentrally located sloping faces 38 of the upper bevelled portion 36define the lower surfaces of the keyways 30.

FIGURES 4-6 are illustrative of a representative column 40 which isassembled with the blocks 20 in cases in which the blocks are to be usedin the floor of a building. The column 40 preferably is cast in onepiece from concrete or similar material and includes an upstandingportion 42 and a substantially flat upper portion 43. The upper portion43 is of a configuration which is similar in some respects to that ofthe block 20. Thus, the portion 43 is provided with a square peripheralflange 45 having an upper bevel 46 and a lower bevel 47 which correspondto the bevels 36 and 37 on the block flange 35. However, the portion 43is substantially thinner than the block 20 and includes an extension 48which protrudes upwardly from the columnar portion 42. The verticaldimension of the extension 48 is slightly less than the thickness of theblock.

The column 40 is of square cross section, and the upstanding portion 42thereof is provided with a series of reinforcing rods 50. The rods 50are surrounded at intervals by straps 51 (FIGURES 9 and 10), and theupper ends 52 of the rods protrude from the column extension 48 and arebent over at right angles with respect to the major portions of therods.

As best shown in FIGURES 7 and 8, the concrete blocks 20 are arranged atthe building site in contiguous relationship with each other to form asubstantially planar building slab 55. The blocks are temporarilysupported at the site (by means not shown) to form a grid-like patternwith the peripheral flanges 35 of adjacent blocks in substantial contactwith each other and with the side walls 26 facing one another to definea V-shaped groove 56 therebetween. In cases in which the slab 55 is tobe used to form the floor of the building, the upstanding columns 40 areassembled at intervals in the pattern of blocks. The upper portion 43 ofeach column is arranged in the plane of the slab with its peripheralflange 45 in contact with the peripheral flanges 35 of the adjacentblocks. The extensions 48 of the columns protrude upwardly from theportions 43 to a level slightly beneath the upper faces 22 of theblocks.

A series of horizontal reinforcing rods 57 are disposed in the V-shapedgrooves 56 between the adjacent blocks 20. As best shown in FIGURE 11,the rods 57 are arranged in spaced-apart pairs and are interconnected bytransverse rods 58 to form a ladder-like construction. The rods 58extend in vertical planes in directions which meet the horizontal planeof the slab 55 at acute angles. The horizontally extending end portions59 of the rods 57 adjacent the column extensions 48 (FIGURES 5 and 7)may be suitably afiixed to the upper ends 52 of the column reinforcingrods 50.

After the reinforcing rods 57 and 58 have been inserted in the V-shapedgrooves 56, concrete 60 or other cementitious material is poured intothe grooves and over the upper faces of the column portions 43. Theconcrete which is poured over the portions 43 is disposed around theextensions 48 of the columns and is flush with the upper faces 22 of theblocks 20, thus concealing the eX- tensions therebeneath. The concretein the grooves 56 extends into the keyways 30 to form shear keys 62.Because of the unique configuration of the keyways 30, these shear keys,in addition to resisting shear stresses in the plane of the buildingslab 55, also resist such stresses in directions perpendicular to theplane of the slab. Thus, for floor slabs of the type shown in FIGURES 7and 8, for example, the shear keys 62 resist both horizontal andvertical shear stresses. The arrangement is such that the blocks 20 arenot merely fillers for the poured-in-place concrete 60 but perform animportant load-supporting function, as does the concrete. The blocks andthe concrete act together to provide a monolithic structural unitcapable of withstanding surprisingly high shear stresses.

The bevelled portions 36 and 37 on the peripheral flanges 35 greatlyfacilitate the alignment of the individual blocks 20 in substantiallycoplanar relationship with each other, while the bevelled portions 46and 47 on the columns 40 similarly facilitate the alignment of thecolumns with the blocks. In addition, in cases in which the lower faces23, for example, of the blocks are to be left exposed, the bevelledportions 37 and 47 produce a pleasing grid-like pattern on the thusformed ceiling, and the bevels have the effect of minimizing slightdifferences in the level of the individual blocks.

As indicated heretofore, each of the blocks 20 is provided with aninternal cavity 21 (FIGURE 2) to form a hollow construction. With thisarrangement, the blocks are comparatively light in weight and may bereadily transported from the factory to the building site. The cavities21 illustratively are formed through the use of cardboard boxes orsuitable foam materials which serve as internal molds and are retainedin the blocks. The boxes, foam materials or other internal molds may beprovided with suitable sleeves which define openings for the posts 25.The resulting hollow construction produces relatively thin side walls 26for the blocks and even thinner central portions 33 as a result of thekeyways 30. At the construction site, selected ones of the portions 33may' be readily removed prior to the pouring of the concrete 60 toprovide convenient access to the interiors of the blocks. The necessaryelectrical wiring, plumbing and heating and cooling ducts for thebuilding may be quickly and easily inserted through the thus formedopenings in the blocks and concealed between the opposed block faces 22and 23.

In certain advantageous embodiments of the invention, the peripheralflanges on the blocks are notched to provide even further resistance toshear stresses in the plane of the building slab. In the embodimentshown in FIG- URE 12, for example, adjacent concrete blocks 65 includeperipheral flanges 66 which each have three bevelled surfaces 67, 68 and69 thereon. The surfaces 67 and 68 correspond to the bevelled surfaces36 and 37 (FIGURE 1) of the building blocks 20 described above, whilethe surface 69 slopes upwardly from the side wall of the block to forman abrupt edge 70 with the surface 68. The edge 70, together with thesurface 69 of the adjacent side wall, defines a notch 72. Upon thepouring of cementitious material 73 between the adjacent blocks, thematerial extends into the notch 72 to provide a positive lock betweenthe blocks and thereby further reduce the possibility of the blocksbecoming separated as a result of excessive shear stresses in the planeof the building slab.

FIGURE 13 is illustrative of one form of apparatus useful in themanufacture of the preformed building blocks at the factory. Althoughthe apparatus may be arranged to produce either the blocks 20. of FIGURE1 or the blocks 65 of FIGURE 12, in the specific form shown in FIGURE 13the apparatus is adapted to manu facture blocks of the type indicated at75. The blocks 75 are generally similar to the blocks 20 (FIGURES 1-3)but are somewhat thicker and do not include the lower faces 23, theblocks 75 being left open to provide a honeycomb appearance in cases inwhich they are assembled into an exposed floor slab, for example.

The blocks 75 are formed through the use of a series of core molds 76which define internal cavities 77 for the blocks. Successive molds 76are automatically led by an infeed conveyor belt 78 to a verticallymovable platform 80 which may be raised or lowered through the use ofhydraulic jacks 81. Upon the receipt of each successive mold on theplatform 80, the platform is lifted by the jacks 81 from the level ofthe infeed conveyor 78 to a position (the position shown) immediatelybeneath a pouring chute 85. The chute 85 includes an upper section 86and two telescoping conical sections 87 and 88 disposed therebeneath.

The external side walls, keyways and flanges of the block 75 are formedby four plates 89. The plates 89 advantageously comprise vacuum mats ofa type well known in the art and are connected by conduits 95 to asuitable vacuum pump (not shown). Each plate is movable toward and awayfrom the core mold 76 by a hydraulic jack 96. As the platform 80 reachesits upper position, the jacks 96 move the plates 89 toward the mold 76to position the plates in spaced juxtaposition therewith.

Concrete is then poured into the pouring chute 85. The concrete flowsthrough the chute section 86 and is directed outwardly along the conicalsurfaces of the sections 87 and 88 into the spaces between the vacuumplates 89 and the core mold 86, thereby forming the completed block.During the pouring of the concrete, the platform 80 and the mold 86advantageously are vibrated by a vibrator of conventional construction.

After the pouring operation has been completed, the vacuum pump isenergized to apply suction through the conduits to the side plates 89and thereby facilitate the curing of the concrete by the removal ofexcess moisture therefrom. The plates 89 are then stripped outwardlyaway from the completed block by the jacks 96, and the jacks 81 areenergized to return the platform 80 to its initial position at the levelof the infeed conveyor 78. The completed block is carried from theapparatus by an outfeed conveyor 97 for storage and eventualtransportation to the building site.

The apparatus of FIGURE 13 preferably is arranged for semi-automaticoperation, with the conveyor speeds, the actuation of the jacks 81 toraise the platform 80, the movement of the side plates 89 into castingposition by the jacks 96, the energization of the vibrator 90, thepouring of the concrete, the application of low pressure to the plates89, the stripping of the plates, the lowering of the completed block bythe jacks 81 and the discharge of the blocks onto the outfeed conveyor97 all coordinated in sequential, timed relationship with each other.

In each of the illustrated embodiments of the invention, the precastbuilding blocks advantageously are of square configuration. In othergood arrangements, however, the blocks may be triangular, hexagonal orof other suitable shape consistent with the provisions of keyways in theside walls thereof which enable the formation of shear keys having theunique features described above.

What is claimed is:

1. In a monolithic building structure, in combination, a plurality ofpreformed members having substantially parallel faces and having sidewalls arranged in contiguous relationship with each other to form asubstantially planar building slab, the side walls of adjacent membersbeing angularly disposed with respect to the plane of one face of saidslab and facing each other to define a groove therebetween, each of saidfacing side walls including a keyway having side portions which extendin uniform fiat planes from adjacent said one face of the slab to theother at acute angles with respect to the plane of said one face, eachof said acute angles being of the order of seventy-six degrees, and abody of pouredin-place cementitions material for holding said memberstogether, said cementitions material being disposed in the groovesbetween adjacent members and extending into said keyways to form shearkeys, said shear keys resisting shear stresses in the plane of said slaband also in directions perpendicular thereto.-

2. In a monolithic building structure of the character set forth inclaim 1, said facing side walls being comparatively thin to form ahollow space within each of said members, a portion of each of said sideWalls being thinner than the remaining portion thereof.

3. 'In a monolithic building structure, in combination, a plurality ofpreformed members arranged in contiguous relationship with each other toform a substantially planar building slab, each of said preformedmembers having substantially parallel faces and having a side wallextending in a plane which meets the plane of one face of said slab atan acute angle, the side walls of adjacent members facing each other todefine a generally V-shaped groove therebetween, each of said facingside walls including a keyway having converging side portions whichextend in uniform fiat planes from adjacent said one face of the slab tothe other at acute angles with respect to the plane of said one face,each of the acute angles between the planes of the side portions andsaid one face being less than the acute angle between the plane of saidside wall and said one face, and a body of pouredin-place cementitionsmaterial for holding said members together, said cementitions materialbeing disposed in the V-shaped grooves between adjacent members andextending into said keyways to form shear keys, said shear keysresisting shear stresses in the plane of said slab and also indirections perpendicular thereto.

4. In a monolithic building structure in combination, a plurality ofpreformed members arranged in contiguous relationship with each other toform a substantially planar building slab, each of said preformedmembers having substantially parallel faces and a peripheral flangeadjacent one of said faces, each said member including a side wallextending in a plane which meets the plane of said one face at an acuteangle, the peripheral flanges of adjacent members being in substantialcontact with one another and the side walls of adjacent members facingeach other to define a generally V-shaped groove therebetween, each ofsaid facing side walls including a keyway having side portions whichintersect the other face of the corresponding member and extend inuniform flat planes from said other face to said peripheral flange atacute angles with respect to the plane of said one face, each of theacute angles between the planes of the side portions and said one facebeing less than the acute angle between the plane of said side wall andsaid one face, and a body of poured-in-place cementitions material forholding said members together, said cementitions material being disposedin the V-shaped grooves between adjacent members and extending into saidkeyways to form shear keys, said shear keys resisting shear stresses inthe plane of said slab and also in directions perpendicular thereto.

5. In a monolithic building structure of the character set forth inclaim 4, the peripheral flange of each of said preformed members beingbeveled to form at least one sloping surface on each flange.

6. A precast building block adapted to be assembled for cementitionsinterlock with other blocks in a substantially planar building slab,said block being of integral, one-piece construction and havingsubstantially parallel faces and a plurality of side walls extending inplanes which are each disposed at an acute angle with respect to theplane of one face of said slab, each of said side walls defining akeyway having a fiat central portion parallel to the corresponding sidewall and having converging side portions which extend in uniform flatplanes from adjacent said one face of the slab to the other at acuteangles with respect to the plane of said one face, each of the acuteangles between the planes of the side portions and said one face beingless than the acute angle between the plane of the corresponding sidewall and said one face, said side walls being comparatively thin to forma hollow space within said block and said central portions being thinnerthan said side walls, whereby when cementitions material is inserted insaid keyway a shear key is formed between juxtaposed such blocks whichresists shear stresses in the plane of said slab and also in directionsperpendicular thereto.

7. A precast building block adapted to be assembled for cementitionsinterlock with other blocks in a substantially planar building slab,said block being of integral, one-piece construction and includingsubstantially parallel faces, said block having a peripheral flangeincluding a beveled edge portion adjacent one of said faces and aplurality of side walls extending in planes which are each disposed atan acute angle with respect to the plane of said one face, each of saidside walls defining a keyway having a flat central portion parallel tothe corresponding side wall and having converging side portions whichintersect the other of said faces and extend in uniform fiat planes fromsaid other face to said peripheral flange at acute angles with respectto the plane of said one face, each of the acute angles between theplanes of the side portions and said one face being less than the acuteangle between the plane of said side wall and said one face, said keywayforming a shear key upon the insertion of cementitions material therein,and between juxtaposed such blocks which resists shear stresses in theplane of said slba and also in directions perpendicular thereto.

8. A precast building block of the character set forth in claim 7, thebeveled edge portion of said peripheral flange forming a plurality offlat sloping surfaces in converging relationship with each other.

9. A precast building block of the character set forth in claim 8, theportion of said peripheral flange adjacent each side wall includingfirst and second upwardly sloping surfaces on opposite sides thereof anda downwardly sloping surface which intersects one of said upwardlysloping surfaces to form a peripheral notch on said flange.

10. A monolithic building structure comprising, in combination, aplurality of preformed members arranged in contiguous relationship witheach other to form a substantially planar building slab, each of saidpreformed members having substantially parallel faces and having asloping side wall extending in a plane which meets the plane of one faceof said slab at an acute angle, the side walls of adjacent membersfacing each other to define a generally V-shaped groove therebetween,each of said facing side walls including a keyway having converging sideportions which extend in uniform flat planes from adjacent said one faceof the slab to the other at acute angles with respect to the plane ofsaid one face, each of the acute angles between the planes of the sideportions and said one face being less than the acute angle between theplane of the corresponding side wall and said one face, means includinga plurality of upright preformed columns for supporting said slab, eachof said columns including an upper section extending in the plane ofsaid slab, and a body of poured-in-place cementitious material forholding said members and said columns together, said cementitionsmaterial being disposed in the V-shaped grooves between adjacent membersand extending into said keyways to form shear keys,

said shear keys resisting shear stresses in the plane of said slab andalso in directions perpendicular thereto.

11. A monolithic building structure of the character set forth in claim10, in combination, reinforcing means disposed in said V-shaped grooves,said reinforcing means including a first series of reinforcing rodsextending in directions parallel to the plane of said slab and a secondseries of reinforcing rods which are angularly disposed with respect tothe plane of said slab.

12. A monolithic building structure comprising, in combination, aplurality of precast concrete blocks having substantially parallel facesarranged in contiguous relationship with each other to form asubstantially planar floor slab for a building, each of said concreteblocks having a substantially square peripheral flange and a pluralityof oppositely disposed side walls extending in planes which meet theplane of said slab at an acute angle A, the peripheral flanges ofadjacent blocks being in contact with one another and the side walls ofadjacent blocks facing each other to define a generally V-shaped groovetherebetween, each of said facing side walls including a keyway having afiat central portion parallel to the corresponding side wall and havingconverging side portions which each extend in uniform flat planes fromadjacent one face of the corresponding block to the other at an acuateangle B with respect to the plane of said slab, said acute angle -Bbeing less than said acute angle A, said side walls being comparativelythin to form a hollow space within each of said blocks and said centralportions being thinner than said side walls,

disposed in the V-shaped grooves between adjacent members and extendinginto said keyways to form shear keys, said shear keys resisting shearstresses in the plane of said slab and also in directions perpendicularthereto.

13. A monolithic building structure of the character set forth in claim12, each of said columns including an extension disposed above saidupper section, said cementitious material being disposed on said uppersection and surrounding said extension to rigidly bond the same to theadjacent blocks.

14. A monolithic building structure of the character set forth in claim12, in which the flange on each of said blocks and the upper section ofeach of said columns are provided with beveled peripheral portions, thebeveled peripheral portion of each column being in abutting relationshipwith the beveled peripheral portions of the adjacent blocks.

References Cited UNITED STATES PATENTS 1,353,373 9/ 1920 Allbright52-337 X 1,389,404 8/ 1921 White 52-577 X 1,397,147 11/1921 Sawyer52-324 X 1,776,572 9/ 1930 Tise 52-440 FOREIGN PATENTS 878,395 10/1942France.

805,071 5/1951 Germany.

547,340 5/ 1956 Belgium.

FRANK L. ABBOTT, Primary Examiner P. C. FAW, JR., Assistant ExaminerU.S. Cl. X.R.

